Judgment in relation to the doctrine of equivalents made by the large collegiate body of the Intellectual Property High Court

Judgment made by the Intellectual Property High Court on March 25, Heisei 28 (2016) (Heisei 27 (2015), “Ne” No. 10014)
A case demanding the suspension of patent infringement

1. Background and summary

The subject case is a case in which a demand for the suspension of the import, sales, etc. of a formulation, etc. is approved based on a patent right, for the reason that the method of producing the formulation, etc. is equivalent to the patented invention.

In the original instance (Tokyo District Court, Heisei 25 (2013), “Wa” No. 4040), the original pharmaceutical manufacturer (plaintiff in the original instance/appellee in the subject case), who is one of the co-owners of Japanese Patent No. 3310301 (Title of Invention: “Intermediates for synthesis of vitamin D and steroidal derivatives and methods of producing the intermediates”), claims that the method for producing the active pharmaceutical ingredient of maxacalcitol or the formulation of maxacalcitol which are imported and/or sold by the four generic pharmaceutical manufacturers (defendants in the original instance/appellants in the subject case) is equivalent to the patented invention and belongs to its technical scope, hence seeking an injunction against import, assignment, etc. of the defendants’ products and their destruction as well. Tokyo District Court accepted the plaintiff’s demand by holding that the defendants’ method is equivalent to the patented invention as satisfying Requirements 1-5 for equivalency.

Dissatisfied with the original decision, the defendants (appellants) filed the subject appeal. The large collegiate body of the Intellectual Property High Court, holding as in the original instance that the appellants’ method is equivalent to the patented invention, dismissed the appeal.

It is worth noting in the court decision of the subject appeal that its findings include general ideas about Requirements 1 and 5 for the doctrine of equivalents.

2. Judgment made by the Intellectual Property High Court

(1) Five requirements for equivalency

The five requirements for equivalency are the following which were set out in the “Supreme Court Judgment in the Ball Spline Bearing Case” (judgment made by the Third Petty Bench of the Supreme Court on February 24, 1998 (Heisei 10) (Heisei 6, “O” No. 1083)) are as follows:

Requirement 1 (Non-essential part):
A difference between the patented invention and the allegedly infringing product, etc. is not an essential part of the patented invention.

Requirement 2 (Replaceability):
Even if such difference is replaced with a corresponding part of the allegedly infringing product, etc., the objective of the patented invention can be attained to exert the same effect and action.

Requirement 3 (Ease of replacement):
The above-mentioned replacement could have readily been conceived by any person skilled in the art at the time of production of the allegedly infringing product, etc.

Requirement 4 (Ease of conception):
The allegedly infringing product, etc. is neither identical to the known art at the time of the filing nor could have readily been conceived from the same by any person skilled in the art.

Requirement 5 (Special circumstances):
There are no special circumstances, such as where the allegedly infringing product, etc. is something that was intentionally excluded in the prosecution of application.

The burden of proof of Requirements 1-3 rests on the person who claims that the allegedly infringing product, etc is equivalent to the patented invention (i.e. patentee) and the burden of proof of Requirements 4 and 5 rests on the person who denies the application of the doctrine of equivalents, and this is again affirmed in the court decision of the subject appeal.

(2) Finding about Requirement 1 for equivalency

Regarding Requirement 1, the large collegiate body of the Intellectual Property High Court held that the essential part of a patented invention is that characteristic part of the disclosures in the Scope of Claims of the patented invention which constitutes a unique technical idea that is not seen in the prior art and that the identity of such characteristic part should be established by means of comparison between the disclosures in the Scope of Claims and those in the specification, especially the description of the prior art in the latter. Further holdings of the large collegiate body are that the establishment of the essential part may be affected by how much contribution the patented invention makes to the prior art, and that when disclosures about the prior art in the specification are insufficient from an objective viewpoint, the essential part should be established by also taking into account the prior art that is not described in the specification.

The large collegiate body of the Intellectual Property High Court also held that the process of determining whether the difference between the patented invention and the allegedly infringing product, etc. is a non-essential part or not should not be such that each of constituent features recited in the Scope of Claims are divided into an essential part(s) and a non-essential part(s), with the doctrine of equivalents being applied in no way to a constitution that corresponds the essential part, but rather that a check is made to see if the allegedly infringing product, etc. shares the essential part of the patented invention which has been established in the way set forth above. There are two different ways to construe Requirement 1: the “essential part theory” according to which this requirement means that the difference between the constitution recited in the Scope of Claims and the allegedly infringing product, etc is a non-essential part, and the “same technical idea theory” according to which this requirement means that the allegedly infringing product, etc. as a whole which includes a substituted part is within the scope of the technical concept of the patented invention; the holding set forth above is believed to support the idea of “same technical theory,” which is currently regarded as a prevailing theory.

(3) Finding about Requirement 5 for equivalency

Regarding Requirement 5, the large collegiate body of the Intellectual Property High Court held that even if there is another constitution that any person skilled in the art could have readily conceived of at the time of filing as one that was substantially identical to the constitution recited in the Scope of Claims, this fact alone cannot serve as a reason for alleging that the applicant’s failure to recite said another constitution in the Scope of Claims falls under the “special circumstances” in Requirement 5. On the other hand, the large collegiate body held that if the applicant is objectively and externally deemed as having recognized another constitution that is outside the Scope of Claims as a replacement of a different part of the constitution recited in the Scope of Claims at the time of filing, the applicant’s failure to recite said another constitution in the Scope of Claims falls under the “special circumstances” in Requirement 5.

Here, the large collegiate body cites two examples of the case where the applicant is objectively and externally deemed as having recognized another constitution that is outside the Scope of Claims as a replacement of a different part of the constitution recited in the Scope of Claims and they are: (a) the case where the applicant is considered to have described the invention based on said another constitution in the specification and (b) the case where the applicant described, in a paper, etc. which they published at the time of filing, the invention based on another constitution that is outside the Scope of Claims.

3. Potential impacts on patent practice

Given the fact that there have been very few cases, and almost no chemical cases, of patent infringement lawsuits in which equivalency is acknowledged for the patentee who then becomes a winner, the subject case deserves particular attention as one where equivalency is acknowledged for the patented invention which hence is recognized to have been infringed.

Regarding Requirement 5, the circumstances that fall within the category of intentional exclusion are exemplified by: (a) the case where another constitution is described in the specification but not in the Scope of Claims and (b) the case where the invention based on another constitution that is outside the Scope of Claims was described in a paper, etc. which the applicant published at the time of filing; this means the applicant should be careful, more than ever, about the way in which the invention being applied for patent and any related information are disclosed, including disclosures in scientific papers and all other means than patent application.